Regulator system



DEC. 3, 1940. s SPRQNG 2,224,067

REGULATOR SYSTEM Original Filed April 19, 1938 Inventor: Sev rn D.Sprong,

by y m His Attovn e3.

Patented Dec. 3, 1940 UNITED STATES PATENT OFFICE General Electric ComNew York pany, a corporation of Application April 19, 1938, Serial No.202,887 Renewed April 20, 1940 Claims.

This invention relates to regulator systems and more particularly toimprovements in voltage regulating means for systems of electricaltransmission and distribution.

5 The present invention is an improvement on that disclosed and claimedin my co-pending joint application with Louis F. Blume, Serial No.202,892, filed April 19, 1938, and assigned to the assignee of thepresent application. In that aploj plication, a novel regulator systememploys as its principal element a novel line drop responsive controldevice for a regulator.' In accordance with the present invention Iprovide another form of line drop responsive regulator control 16)means.

i It is an object of this invention to provide a new and improvedregulator system.

It is another object of this invention to provide a new and improvedline drop responsive regulator control arrangement.

Theinvention will be better understood from the following descriptiontaken in connection with the accompanying drawing and its scope will bepointed out in the appended claims.

Referring now to the single figure of the accompanying drawing, which isa diagrammatic illustration of an embodiment of the invention, there isshown therein a main alternating current power circuit I in which isinserted a regulating transformer 2 provided with a tap changing switch3 for changing the transformer ratio and thus inserting various valuesof regulating voltage in the main circuit. This switch is operated by acontrol device 4 and it may either be 35 operated directly therebythrough suitable reduction gearing 5 or it may be operated indirectlythereby through control contacts and a separate operating motor, as willbe well understood by those skilled in the art.

Device 4 comprises an induction disk 6 provided with a pair of opposedoperating elements I and 8 energized, respectively, in accordance withthe voltage on the supply side of transformer 2, preferably through apotential trans- 45 former 9, and on the load side of the regulatingtransformer 2, preferably through another potential transformer N. Inthe energizing circuit of the element 8 there is inserted a line dropcompensator II which is energized in accordance with the load current bymeans of a current transformer l2.

The operation of the illustrated embodiment of the invention is asfollows. When the line drop compensator II is adjusted to produce avoltage which bears the same relation to the output voltage of thepotential transformer H) as exists between the output voltage of theregulating transformer 2 and the actual line drop between the regulatorand the load, the control device 4 will only balance or be at rest whenthe load voltage is equal to the voltage on the input side of theregulator. Under all other conditions a net torque tends to rotatedevice 4 in one direction or the other. These directions of rotation areso correlated to the switch 3 that they 10 cause the switch 3 to move inthe proper direction to produce a balanced condition in the controldevice 4. Thus, it will be seen that mere fluctuations in the voltagelevel of circuit I will have no substantial effect upon the controldevice 4, whereas changes in load will cause the control device tooperate the regulator so as to produce a regulating effect which exactlycompensates for the line drop caused by the load current.

The above described arrangement holds constant voltage at a point on theload side of the regulator only if the voltage is maintained constant atthe input terminals of the regulator. This may not always be the case assometimes it is more convenient to maintain constant voltage at someother point on the circuit further back toward the generator end. Insuch cases a line drop compensator i3 is provided for element 1. Asshown, this compensator is energized by a current transformer M. It isadjusted so as to compensate element 1 for the line drop between theconstant voltage point and the input terminals of the regulator. Undernormal conditions its voltage will usually add to the voltage ofpotential transformer 9 whereas under the same conditions the voltage ofcompensator II will usually subtract from. the voltage of potentialtransformer ID. The result is that the amount of voltage inserted in thecircuit by the regulator is increased enough to compensate for thevoltage drop between the constant voltage point and the regulator. Theload voltage is therefore independent of changes in current.

It will also be noted that the speed of the control device 4 will beroughly proportional to the net difference in voltage of the two motorelements. This gives a rate of'voltage correction proportional to thedegree of correction necessary.

While the invention has been shown in connection with a step typeregulator, it will be understood that it may equally well be applied tooperating any other suitable type of regulator, 55

such, for example, as an induction voltage regulator.

While there has been shown and described a particular embodiment of thisinvention, it will be obvious to those skilled in the art that variouschanges and modifications can be made therein without departing from theinvention and, therefore, it is aimed in the appended claims to coverall such changes and modifications as fall within the true spirit andscope of the invention.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. In a regulator system, power transmitting and distributing apparatushaving a variable quantity to be regulated, a regulator therefor havingan input side and an output side, a primary device for controlling theoperation of said regulator, said device having means for urging it inone direction in accordance with the value of said quantity on the inputside of the regulator and having means for urging it in the oppositedirection in accordance with the difference between the value of saidquantity on the output side of said regulator and the drop in value ofsaid quantity resulting from the transmission and distribution of powerover a given distance from said regulator.

2. In combination, anelectrie circuit, means for regulating the voltageof said circuit and control means for said regulating means, saidcontrol means including a pair of opposed normally balanced operatingwindings connected respectively to respond to said circuit voltage onopposite sides of said regulating means, and

means for inserting a voltage in series with one of said windings whichis proportional to the voltage drop in a predetermined length of saidcircuit.

3. In combination, an alternating current circuit, a variable ratioregulating transformer connected in said circuit, a reversible controlmotor connected for direct mechanical operation of said regulatingtransformer, said motor having means responsive to the voltage on theinput side of said transformer for urging-it in a direction to causesaid regulating transformer to raise the voltage of said circuit saidcontrol motor having a second means energized in accordance with thevoltage on the load side of said regulating transformer for urging it ina direction to cause said regulating transformer to lower the voltage ofsaid circuit. and means for reducing the voltage on said last mentionedoperating means in accordance with the line drop in a predeterminedamount of said circuit.

4. In a regulating system, an electric circuit which transmits powerfrom a first point thereon to a second point thereon, said circuithaving a substantial current carrying impedance between said points, andvoltage regulating means including a normally balanced device havingopposed elements responsive respectively to the voltages at said pointsfor holding the voltage at the second point at a predeterminedpercentage of the voltage at the first point.

5. In a regulating system, an electric circuit which transmits powerfrom a first point thereling said regulator, a line drop compensator torcompensating one of said elements for the line drop between the firstpoint and said regulator, and a second line drop compensator forcompensating the other element for the line drop between said regulatorand the second point.

SEVER-N D. SPRONG.

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